
Donald W. answered 09/02/22
Experienced and Patient Tutor for Math and Computer Science
I think what they want you to do is to combine these two equations together twice to get two equations: one in terms of x and z and another in terms of y and z. Then you can use those to express x and y in terms of z. For example, if you did this for x, you'd get:
x = (54 - 23z)/13
Then you can use those to write the answer as:
(x, y, z) = ( (54-23z)/13, <y in terms of z>, z )
Can you finish this by finding out what y is in terms of z?